Steam-engine



H. A. STRINGFELLOW AND E. W. TEMPLIN.

STEAM ENGINE.

APPLICATION FILED OCT. 11. 1915.

Patented Aug. 24, 1920.

I ATTORNEY.

UNITED STATES PATENT OFFICE.

HENRY A 'STRINTGFELLOW AND ELLI$ W. TEMPLIN, OF ROCHESTER, NEW YQRK.

STEAM-ENGINE.

T 0 all whom may concern:

Be it known that we, HENRY A. S'rn'tne FELLOW and Eilms VV.;TEI\I1?LIN, of Rochester, in the countyof'Monroe and State of New length. In the presentembodiment of the York, have inventedcertain new anclnseful Improvements in Steam-Engines; and we do hereby declare the .i ollowing to be a full,

clear, and exact description .ojfthe same, ref-j erence being 'had'to the z'icconip'anying drawings, forming afpart ofthisfspecification, and to the referencenumerals marked thereon. I 5

Our present invention relates to steam en-f. gines and more'particularly: to engines of" what is known; as the Una-flow typ ewhere the admission of steam to' thepiston occurs at both ends of thecylinderfwhile the exhaust occurs nearthe'jmiddle ofthe cylinder or at 'a point-midway of'the limits of travel of thepiston and the invention has for its object to materially reduce the weight of the engine by shortening both the cylinder and the piston while preserving-a given length of piston stroke; to permit the attainment of higher piston'speeds and to increase the general efliciency of the engine by providing greater flexibility in the ad-.

justment of the cut-ofl' and'b'y reducing the time during which the cylinder is-subjected to exhaust temperatuire- To-theseand other ends the invention resides in certain improvements and comblnationsofparts, all as will be hereinafter more fully described, the

novel features being' pointed out in the claims at the end of the specification.

In the drawings: 7 V v Figure 1 is a longitudinal central section through the cylinder-and'admission valve of a steam engine constructed in accordance with and illustratingone.embodiment of our invention, and I Fig. 2 is a transverse" section taken substantially on the line' of Fig. 1. 7

Similar reference numerals throughout the several figures indicate the samejparts.

The usual type of una'-flo'w -'engine em- 7 ploys a heavy block piston w-hich itself control's the central exha-ust' port. The cut-off face thereof is at some distance from the steam face and the added length of the cylinder required to accommodate it for the full stroke,'together with the necessary size of the piston itself makes the aggregate weight and size excessive. In the practice of our present invention, we control the exhaust port independently of the piston by a relatively thereto sotha-t an ordinary disk piston can be used for the same stroke with in a cylinder, of approximately half the ings, 1indicatesa saddle casting that supportsthe bol'ler and carries a cylinder 2 Specification of Letters Patent. Patented Aug. 2 1, 1920.

Application filed October-11, 1915. Serial No. 55,172.-

jacket'd'at 3 and having the. jacketed heads 7 4-and'5,.the cylinder'andheads being inclosed by lagging .6. An exhaust belt 7 partly surrounds'the centerof the cylinder on the outer side-which belt is expanded on thejinner sidejinto'an exhaust chamber 8.

At the center the cylinder walls are pierced by a plurality of circumferentially arranged exhaust ports 9that open into the belt and Y intothe chamber 8. There is thus provided,

as shown in Fig. 2, a progressively enlarged passage for the escape of the exhaust steam as it accumulates from the various ports, While at the same time the cylinders are not caused to project unduly and increase the width of the locomotive.

The live steam is admitted from the boiler through a passage 10 and manifold 11 to,

both endsof a-cylinder' 12 constituting a,

valve chamber 13 and thence through in take ports 14 and 14 to the opposite ends offthel cylinder 2 under the control. of an outside admission piston valve 15 having an operating ro d 15 or any suitable form of valve may be used. The exhaust ports 9 are controlled by a reciprocating sleeve 16 of about half the length of the cylinder, which is in intimate contact with the Walls of the latter and travels from one end to the other, being so proportioned in length that it will uncover the exhaust port while at its limit of movement at either end. It

I is operated by the steam pressure acting on the exposed end of the sleeve and the rods 17 passing through the cylinder head 5 and connected by a cross head 18 with an operating rod 19 which is connected at a suitable point in the valve gear and serves to synchronize the motion of the sleeve with the motions of the other parts of the engine.

The piston 20 having the rod 21 may be of the ordinary disk type, as shown. At any rate, it is very short, much shorter than the sleeve 16 which latter it fits closely in the manner of an ordinary piston and cylinder and it Works in contact with the sleeve instead of with the cylinder walls 2. The sleeve travels at approximately half the speed of the piston so that there is relative piston. The latter is at the left hand end of the sleeve and the sleeve is at the left hand end of the cylinder with the exhaust ports 9 uncovered. The steam used on the previous stroke is being exhausted through the ports 9 which, because of their size and number, reduce the pressure very rapidly. Both the piston and sleeve now travel to the right. The sleeve, though moving more slowly, closes the exhaust port 9 before the piston has reached the neighborhood thereof and by the time it has so completed its travel that it passes over these ports and opens them again, the piston has reached the right hand end of the sleeve and the sleeve has reached the right hand end of the cylinder ready for an admission of steam at it and repetition of the operation from the other direction.

It is obvious that the compression of the exhaust steam is negligible, it being possible to design the parts so that it is trapped in front of the piston in small volume raised not above boiler pressure at completion of the piston stroke. The exhaust virtually flows out freely and is not driven out by the piston. Other advantages aside from the above mentioned reduction in weight and size, are that the wear of the piston and sleeve is widely distributed at both sides of the sleeve, and renewal of the sleeve after wear compensates for wear of both the cylpiston surface without means for opening and closing the intake ports.

2. In a steam engine, the combination with a cylinder and a piston operating therein, said cylinder being provided with inlet ports at each end and an intermediate exhaust port, of a sleeve arranged to reciproeate in the cylinder between the walls of the latter and the piston and to open and close the exhaust port with each reciprocation of the piston, means independent of the piston for operating the sleeve, and additional means for opening and closing the intake ports.

3. In a steam engine, the combination with a cylinder and a piston operating therein, said cylinder being provided with inlet ports at each end and with an intermediate exhaust port at a point midway of the piston stroke, of a sleeve arranged to reciprocate in the cylinder between the walls of the latter and the piston and to open and close the exhaust port upon each reciprocation of the cylinder, saidsleeve being of a length approximating one half of that of the cylinder. 7 I

HENRY A. STBINGFELLOW. ELLIS W'. TEMPLIN. lVitnesses v RUSSELL B. GRIFFITH, HARRIET T. DAY. 

